When working with network devices, it can be quite useful to validate and match MAC addresses in your Java applications. While there are different MAC address formats, a common pattern consists of six pairs of hexadecimal digits separated by colons or hyphens.

In this blog post, we will explore how to use Java regular expressions to match MAC addresses with different patterns.

Using Java Regular Expressions

Java provides the Pattern and Matcher classes in the java.util.regex package, which allow us to work with regular expressions.

To match a specific MAC address pattern, we can construct a regular expression and use it in combination with the Pattern and Matcher classes.

Here’s an example of how we can match MAC addresses with different patterns:

import java.util.regex.*;

public class MacAddressMatcher {
    public static boolean isMacAddressValid(String macAddress) {
        String pattern = "^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$";

        Pattern macPattern = Pattern.compile(pattern);
        Matcher matcher = macPattern.matcher(macAddress);

        return matcher.matches();
    }

    public static void main(String[] args) {
        String[] macAddresses = {
            "00:11:22:33:44:55",
            "00-11-22-33-44-55",
            "AA:BB:CC:DD:EE:FF",
            "AA-BB-CC-DD-EE-FF",
            "001122334455",
            "AABBCCDDEEFF"
        };

        for (String macAddress : macAddresses) {
            if (isMacAddressValid(macAddress)) {
                System.out.println(macAddress + " is a valid MAC address");
            } else {
                System.out.println(macAddress + " is NOT a valid MAC address");
            }
        }
    }
}

In this example, we define a isMacAddressValid method that takes a MAC address as input and uses a regular expression pattern to validate it. The regular expression ^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$ matches MAC addresses with six pairs of hexadecimal digits separated by colons or hyphens.

We then test this method with a few sample MAC addresses and print whether each one is valid or not.

Conclusion

Using Java regular expressions, we can easily validate and match specific MAC address patterns in our applications. By leveraging the Pattern and Matcher classes, we can define custom regular expression patterns and apply them to MAC addresses for validation and matching purposes.

Remember to import the java.util.regex package and use the Pattern and Matcher classes when working with regular expressions in Java.

#java #regex